NPCs composing that spawngroup :

an_apparition (25%)

greater_spurbone (25%)

greater_spurbone (25%)

greater_spurbone (25%)

NPCs spawning around that spawngroup :
(Max range : 100)

citymist_46, range=65 (66,65,2)

citymist_55, range=83 (24,-45,2)

citymist_66, range=53 (143,-6,274)

a_deranged_madman (50%)
greater_plaguebone (50%)

citymist_67, range=65 (31,-24,274)

greater_war_boned_skeleton (100%)

citymist_74, range=75 (150,-42,273)

citymist_119, range=55 (140,-21,-9)

citymist_133, range=88 (13,46,28)

citymist_172, range=72 (102,-67,2)